NetBSD/gnu/usr.bin/gzip/zip.c

118 lines
3.1 KiB
C

/* zip.c -- compress files to the gzip or pkzip format
* Copyright (C) 1992-1993 Jean-loup Gailly
* This is free software; you can redistribute it and/or modify it under the
* terms of the GNU General Public License, see the file COPYING.
*/
#ifdef RCSID
static char rcsid[] = "$Id: zip.c,v 1.2 1993/10/15 23:06:01 jtc Exp $";
#endif
#include <ctype.h>
#include <sys/types.h>
#include "tailor.h"
#include "gzip.h"
#include "crypt.h"
#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif
#ifndef NO_FCNTL_H
# include <fcntl.h>
#endif
local ulg crc; /* crc on uncompressed file data */
long header_bytes; /* number of bytes in gzip header */
/* ===========================================================================
* Deflate in to out.
* IN assertions: the input and output buffers are cleared.
* The variables time_stamp and save_orig_name are initialized.
*/
int zip(in, out)
int in, out; /* input and output file descriptors */
{
uch flags = 0; /* general purpose bit flags */
ush attr = 0; /* ascii/binary flag */
ush deflate_flags = 0; /* pkzip -es, -en or -ex equivalent */
ifd = in;
ofd = out;
outcnt = 0;
/* Write the header to the gzip file. See algorithm.doc for the format */
method = DEFLATED;
put_byte(GZIP_MAGIC[0]); /* magic header */
put_byte(GZIP_MAGIC[1]);
put_byte(DEFLATED); /* compression method */
if (save_orig_name) {
flags |= ORIG_NAME;
}
put_byte(flags); /* general flags */
put_long(time_stamp);
/* Write deflated file to zip file */
crc = updcrc(0, 0);
bi_init(out);
ct_init(&attr, &method);
lm_init(level, &deflate_flags);
put_byte((uch)deflate_flags); /* extra flags */
put_byte(OS_CODE); /* OS identifier */
if (save_orig_name) {
char *p = basename(ifname); /* Don't save the directory part. */
do {
put_char(*p);
} while (*p++);
}
header_bytes = (long)outcnt;
(void)deflate();
#if !defined(NO_SIZE_CHECK) && !defined(RECORD_IO)
/* Check input size (but not in VMS -- variable record lengths mess it up)
* and not on MSDOS -- diet in TSR mode reports an incorrect file size)
*/
if (ifile_size != -1L && isize != (ulg)ifile_size) {
Trace((stderr, " actual=%ld, read=%ld ", ifile_size, isize));
fprintf(stderr, "%s: %s: file size changed while zipping\n",
progname, ifname);
}
#endif
/* Write the crc and uncompressed size */
put_long(crc);
put_long(isize);
header_bytes += 2*sizeof(long);
flush_outbuf();
return OK;
}
/* ===========================================================================
* Read a new buffer from the current input file, perform end-of-line
* translation, and update the crc and input file size.
* IN assertion: size >= 2 (for end-of-line translation)
*/
int file_read(buf, size)
char *buf;
unsigned size;
{
unsigned len;
Assert(insize == 0, "inbuf not empty");
len = read(ifd, buf, size);
if (len == (unsigned)(-1) || len == 0) return (int)len;
crc = updcrc((uch*)buf, len);
isize += (ulg)len;
return (int)len;
}